Autumn Leaves
by purple mangosteen
Summary: A snippet of Harry and Mycroft's life during Sherlock and John's adventure, from A Study in Pink to the Reichenbach Fall. Slash. Established Mycroft Holmes/Harry Potter.
1. Chapter 1

Disclaimer: Sherlock Holmes and properties are owned by Sir Arthur Conan Doyle. Sherlock and properties are owned by BBC One, Mark Gatiss and Steven Moffat. Harry Potter and properties are owned by JK Rowling. I don't make money from writing this fanfiction. The story contains spoiler for both Sherlock and Harry Potter.

**Autumn Leaves**

A Study In Pink

"Sherlock has flatmate now," Mycroft Holmes announced on the dining table that night.

His companion who was also his lover, Harry Potter, replied. "That's good. Although a bit worrying with all the experiment he does. Severed head in the fridge..." he shook his head. "I'm not sure if normal people could stand it."

"Then it's good that his flatmate is a doctor." Mycroft said. "I talked with the good doctor earlier."

This time Harry raised his eyebrow. "Talked?"

"Well, I had my assistant brought him to secluded place so we could converse freely."

"That's called kidnapping, Mycroft." Harry said dryly.

"That's only a matter of wording, dear."

Harry snorted at that then he frowned. "Good doctor?"

"Dr. John Watson, an army doctor. A veteran from Afghan war. He has trust issue but seems. to confide in Sherlock very quickly."

"Did he accept your offer?" At the look Mycroft gave him, Harry said. "Well, don't look at me like that. You tried to do the same with the detective inspector. Well?"

"No, he refused."

Harry smiled knowingly. "If he accepted it then you would question his integrity."

"It's too earlyt decide the next step. I shall oversee their interaction longer."

Harry nodded, agreeing with Mycorft's decision. He hoped that the doctor turned out good for Sherlock's sake. Even though Sherlock was antisocial, a friendship would do him good. In the end, Mycroft didn't need to wait long. Dr. John Watson killed a man to save Sherlock's life and that was enough to prove his worth to Mycroft.

The Blind Banker

They were in Godric Cottage, Harry's country house at Godric Hollow. After the war, Harry and Hermione thought that it would be great idea to build a wizarding village in England, so they chose Godric Hollow. The entire muggle population had been evacuated and now the village only contained wizards, witches and magical creatures. The only exception right now would be Mycroft, who sat across Harry in the open terrace which overlook a huge parcel of land.

They were having afternoon tea together with Teddy. His said godson now was running happily in the ground with Snuffles, a black puppy that was Harry's birthday gift for him. The boy had eaten half of the cakes Winky made so he was quite high on sugar right now.

"So," Harry began. "How is Sherlock doing now?"

Mycroft raised his eyebrow. Usually it was him who told Harry the news about Sherlock. "Quite well," he answered. "He and the doctor is quite a pair."

"That's good to hear," Harry said.

"In fact, business seems bloom for Sherlock ever since he and John become friends."

Harry looked at Mycroft carefully. "Well, you have additional help now."

"The joy of being an older brother." Mycroft quipped.

The Great Game

"John writes a blog about the case Sherlock and he solved," Mycroft informed.

"Really?" Harry asked, intrigued.

"It is quite interesting."

"Hm...I will check it later," he said. Harry had notebook that he kept in Mycroft's house because it was no use in Grimmauld Place or Godric Cottage.

Harry read the blog then. It was interesting as Mycroft put it. And really, did Sherlock really not know that the earth went around the sun? It was hilarious.

The next day, he read on the paper about gas explosion that happened at Baker Street. "Is Sherlock alright?" Harry asked.

"He's fine. I went there this morning." Mycroft replied.

"That means you went there for a case," Harry concluded.

"Well, that's what he does." Mycroft retorted. "And it is national importance."

Harry never asked what happened in the muggle world. If Mycroft wanted to tell him, then it was the man's choice. He wasn't going to pry. It was the same with Mycroft. The man never asked what Harry did in running the wizarding world. They only talked in their capacity when the two worlds collided.

A few days later, he got news that Sherlock and John were almost killed by maniac. The whole world only consulting detective actually was more dangerous than Harry thought.

Author's Note:

My second crossover fanfiction. Sherlock is my latest obsession now. I really can't wait for the third season. So now I decided to write about Harry Potter and Sherlock which pair Mycroft with Harry. He is my favourite character in Sherlock.


	2. Chapter 2

Disclaimer: Sherlock Holmes and properties are owned by Sir Arthur Conan Doyle. Sherlock and properties are owned by BBC One, Mark Gatiss and Steven Moffat. Harry Potter and properties are owned by JK Rowling. I don't make money from writing this fanfiction. The story contains spoiler for both Sherlock and Harry Potter.

**Autumn Leaves**

A Scandal in Belgravia

"What?" Harry couldn't believe his ears. "Sherlock came to the Buckingham Palace wearing only bed sheet?"

Mycroft gave out a long suffering sigh.

Harry laughed out loud. "Oh, the nerve he has!"

"It was lack of decency he has," Mycroft said dryly.

"You stepped on his sheet! You helped exposing him!" Harry laughed again. "If only I see it with my own eyes." He turned to Mycroft. "You do have CCTV camera there, right?"

Mycroft gave him a look.

**XXXXXXXXXX**

It was Christmas and Harry was alone. He had row with Mycroft and left in anger. Still angry, he chose to go to the Weasleys alone. This turned out to be bad decision. Everyone asked where Mycroft was and when they heard that Harry had a fight with Mycroft, they gave him lots and lots of advice and suggestion. Never mind the fact that Harry never asked for it. He should have expected it actually. Mycroft was big hit with the ladies ever since the first time Harry brought the man with him.

"Rough night, eh mate?" Ron said sympathetically.

"You have no idea," he muttered.

Hermione shook her head. "You and Mycroft never fight before. It is bound to happen sometime."

"Yeah," Ron nodded. "Hermione and I bicker all the time."

"That never changes, eh?" Harry said fondly.

"Nope," Ron replied cheerily.

"But seriously Harry, what has happened?" Hermione asked.

He sighed. "Mycroft is really busy these days. Really, really busy. And when at home he's still working. I tried to talk with him but he dismissed me. I got angry and said many things. So..." he trailed off.

"And you just leave him alone on Christmas Eve?" Hermione asked in disbelief.

"Well, he deserves it!" Harry argued.

"He might have something important to do. Mycroft is the British Government after all." Hermione reasoned.

Harry hated it when she did that. He was perfectly fine with being angry with Mycroft before. After much cajoling from Hermione, which Ron wisely chose to stay out from the discussion, Harry finally ran out stem.

When he returned home, Mycroft wasn't there. Did the man go to his office? Harry wouldn't put it passed him. He was contemplating on this when the door opened and Mycroft walked in. For a while they merely stared at each other. Harry was about to ask Mycroft where he went when he remembered that he was the one who left.

"I went to the morgue," Mycroft was the one who broke the silence. "With Sherlock."

"What?" he asked. "Is everything alright?"

"It was for the case," Mycroft explained.

"Oh."

"Am I forgiven?"

He stared at Mycroft and then sighed. "Yes, yes. Just tell me if you have something big next time."

Back then, when they started this, Mycroft had told him that this was the first real relationship he ever had which Harry understood, for someone like Mycroft. Even for Harry, people clamoured to him because he was the Chosen One. Mycroft was the British Government, he had all the power in his hand, that was enough to attract woman and man to his arms.

It was made worse by the lack of emotion that Mycroft had. Except for his younger brother, Mycroft didn't care for anyone else. He and Sherlock were the same. The only difference was Mycroft was really good at pretending. The polite smile and the pleasantries towards people were all fake. In fact that was one of the things Harry shouted at him. He had accused Mycroft that he never cared about Harry too.

In a few steps, Mycroft was already standing in front of him. "Thank you, dear." The man said and leaned forward to kiss him.

Harry kissed him back. He was really glad about the growth spurt he had back in his seventh year.

"And I care about you." Mycroft whispered once they broke the kiss. "Well, you wouldn't wear my ring if I didn't. Care, that is."

Harry looked at the man then kissed Mycroft again. "I know," he said at last.

"So, bed?" Mycroft asked with smile on his face.

"Oh, yes." He replied, pulling Mycroft down with him.

**XXXXXXXXX**

A few months later Mycroft informed him that the case was closed.

"Is she truly dead?" Harry asked.

"No."

Harry looked at him, astonished. "You lied to your brother and John."

"That's why I have John delivered the news. Sherlock would read thorough me in a second."

"And it is alright with you?"'

"Sherlock went to all trouble to help her. I couldn't deny him that."

Harry regarded him. "With you both, it's always so complicated."

The Hounds of Baskerville

When Mycroft's phone rang that morning, Harry didn't think anything. But when he saw Mycroft's exasperated look, he knew it must be from Sherlock.

"He stole access to all area cards that belonged to me and went to secret military place," Mycroft summed the whole thing.

"Well, I did break into the Department of Mysteries when I was fifteen." Harry said as matter of fact.

"And now he wants access to that place for 24 hours," Mycroft said again, palming his face.

"Mycroft, you knew that he stole your card and you let it because you thought it might come in handy for Sherlock one day. So, don't blame him."

The Reichenbach Fall

"You know, I normally would never associate this word with you. But Mycroft Holmes, you are an idiot." Harry said. "How could you just give Moriarty information about your younger brother?"

"He has something that I want." Mycroft replied.

"He has something you thought he has." Harry corrected. "This will end badly."

But Mycroft was calm. Too calm even and that raised Harry's suspicion.

"You planned this, didn't you?" Harry said. "You're very, very protective of Sherlock. It's impossible for you to exploit his childhood to Moriarty. Unless you're planning something. Am I right?"

Mycroft gave him a faint smile. "Good deduction, dear."

Harry sighed. "I hope your plan work."

"It will." Mycroft replied.

The headline in Muggle newspaper was getting worse every day. And to top it, was the news about Sherlock's suicide.

"Where is he now?" Harry asked.

"Who?" Mycroft questioned.

Harry gave him hard look. "Sherlock."

"I don't know."

That confirmed Harry's suspicion that Sherlock was still alive.

"Moriarty threathened to kill John, Lestrade and Mrs. Hudson if Sherlock didn't kill himself. Moriarty even shot himself to ensure that Sherlock didn't have another option. Before Moriarty's men are either captured or killed, Sherlock couldn't return yet."

With his younger brother safety's compromied and the threat of Moriarty's henchmen hanging above his head, Mycroft looked tired and defeated.

"Go to sleep."

Mycroft looked at Harry as if he had lost his mind for daring suggesting him to sleep.

"You're tired. You can't think if you're tired."

"I can," Mycroft argued.

"Yes, you're genius. But I'm serious here. Go to rest, Mycroft."

But Mycroft merely lay on the bed, pretending to be asleep until Harry had enough and forced him to drink Dreamless Sleep potion.

Mycroft remained busy, ordering his subordinates around and calling people to secret mission. All to help his younger brother. And Harry really couldn't stand seeing him like this. A few weeks later, he came to see Mycroft at his office.

"It's a pleasant surprise, dear." Mycroft said, standing from his chair to greet him. "May I inquire as to what bring you here?" the man said, regarding his black Auror uniform. In the Muggle world, it would be Britain Special Defense Force's uniform. He and Hermione had deigned it better for Auror if they also had establishment in the Muggle world. And so, Britain Special Defense Force was created, a league in the MI5 but reported directly to the Prime Minister. Their uniform was inspired from royal navy uniform.

As the answer, he gave Mycroft two brown envelope. "A file about James Moriarty and Sebastian Moran," he explained.

Mycroft stared at him. "My, my. You do realize that you break your own law, don't you?"

It was the law that stated that each world are running on their own without interfering each other. The Dark Lord would be Harry's problem and Moriarty would be Mycroft's problem, basically like that.

"It's my personal doing," Harry replied. "Do you have any idea how hard is that to obtain information about them? Of course, it would be harder if it was done in conventional way."

"Well, thank you then."

"I have delivered the files to him too." Harry said.

"Oh, and how is he?" Mycroft asked casually. But Harry could see that he was really worried about his younger brother.

"He is fine." He replied. "What are you going to do now?"

"We make a plan, my dear. We make a plan."

Author's Note:

My second crossover fanfiction. Sherlock is my latest obsession now. I really can't wait for the third season. So now I decided to write about Harry Potter and Sherlock which pair Mycroft with Harry. He is my favourite character in Sherlock.


End file.
